The Government remains committed to airport expansion in south-east England despite the result of the EU referendum, Transport Secretary Patrick McLoughlin said yesterday.

He insisted that investment in long-term infrastructure "has become more important".

It has been suggested that David Cameron's resignation could mean a further hold-up in the much delayed decision on whether to expand Heathrow or Gatwick airports.

In July last year, the Davies Commission called for airport expansion by 2030 and recommended the building of a third runway at Heathrow.

But in December the Department for Transport announced that further investigation into noise, pollution and compensation would be carried out before a decision was made.

Mr McLoughlin described airport expansion as "one of the big opportunities" for the UK.

Speaking at the National Infrastructure Forum at the Excel exhibition centre, east London, he said: "We remain committed to expansion and we remain committed to delivering runway capacity on the timetable set out by Sir Howard Davies.

"This remains one of the most important decisions for the Government to take."

The bosses of Heathrow and Gatwick also made speeches at the event. Heathrow chief executive John Holland-Kaye said: "Constraints at Heathrow risk us falling behind our European counterparts and if Heathrow falls behind, Britain falls behind."